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dc.contributor.advisorKovar, Desiderioen
dc.creatorMikulak, James Kevinen
dc.date.accessioned2012-02-06T21:31:48Zen
dc.date.available2012-02-06T21:31:48Zen
dc.date.issued2011-12en
dc.date.submittedDecember 2011en
dc.identifier.urihttp://hdl.handle.net/2152/ETD-UT-2011-12-4565en
dc.descriptiontexten
dc.description.abstractSize effects in out-of-plane bending stiffness of honeycomb cellular materials were studied using analytical mechanics of solids modeling, fabrication of samples and mechanical testing. Analysis predicts a positive size-effect relative to continuum model predictions in the flexure stiffness of a honeycombed beam loaded in out-of-plane bending. A method of determining the magnitude of that effect for several different methods of constructing or assembling square-celled and hexagonal-celled materials, using both single-walled and doubled-walled construction methods is presented. Hexagonal and square-celled honeycombs, with varying volume fractions were fabricated in Nylon 12 using Selective Laser Sintering. The samples were mechanically tested in three-point and four point-bending to measure flexure stiffness. The results from standard three-point flexure tests, did not agree with predictions based on a mechanics of solids model for either square or hexagonal-celled samples. Results for four-point bending agreed with the mechanics of solids model for the square-celled geometries but not for the hexagonal-celled geometries. A closed form solution of an elasticity model for the response of the four-point bending configuration was developed, which allows interpretation of recorded displacement data at two points and allows separation the elastic bending from the localized, elastic/plastic deformation that occurs between the loading rollers and the specimen’s surface. This localized deformation was significant in the materials tested. With this analysis, the four-point bending data agreed well with the mechanics of solids predictions.en
dc.format.mimetypeapplication/pdfen
dc.language.isoengen
dc.subjectSize effectsen
dc.subjectOut-of-plane bendingen
dc.subjectElastic bendingen
dc.subjectAdditive manufacturingen
dc.subjectSelective laser sinteringen
dc.subjectHoneycombsen
dc.subjectMechanics of solidsen
dc.subjectNylon 12en
dc.subjectPA12en
dc.subjectBending stiffnessen
dc.subjectMechanical testingen
dc.subjectCellular solidsen
dc.subjectCellular foamsen
dc.subjectFoamsen
dc.subjectSquare-celled honeycombsen
dc.subjectHexagonal-celled honeycombsen
dc.subjectElasticityen
dc.titleSize effects in out-of-plane bending in elastic honeycombs fabricated using additive manufacturing : modeling and experimental resultsen
dc.date.updated2012-02-06T21:32:06Zen
dc.identifier.slug2152/ETD-UT-2011-12-4565en
dc.contributor.committeeMemberTaleff, Eric M.en
dc.contributor.committeeMemberRodin, Gregory J.en
dc.contributor.committeeMemberBourell, David L.en
dc.contributor.committeeMemberHaberman, Michael R.en
dc.description.departmentMaterials Science and Engineeringen
dc.type.genrethesisen
thesis.degree.departmentMaterials Science and Engineeringen
thesis.degree.disciplineMaterials Science and Engineeringen
thesis.degree.grantorUniversity of Texas at Austinen
thesis.degree.levelDoctoralen
thesis.degree.nameDoctor of Philosophyen


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